Drill tailings and cuttings covered with drilling mud and/or oil and which emanate from an oil derrick, are typically conveyed from the drilling derrick via shaker tables or powered conveyor belts to an interim recirculation bin or temporary storage vessel, prior to being supplied to tailings cleaning apparatus mounted on portable skids.
Due to highway load carrying restrictions [currently for some roads a tri-axle limitation of 55,000 pounds (21,653 kg) for trucks which transport tailings equipment cleaning apparatus to a drill site], the size of recirculation bins and as well the tailings cleaning skids (which possess such cleaning equipment as centrifuges or conical cyclone separators) is typically limited due to such load restriction placed on such trucks, as to is the size of such equipment which can be transported on such trucks. Accordingly, due to the necessary compact size of such equipment, the processing capacity of such equipment is often seriously limited.
Frequently, when rapidly drilling, or when entering a “pay” zone where oil is encountered, a drilling derrick may for a relatively short period of time generate a large quantity of drill tailings and/or tailings which may be very “dirty” or oily.
In such circumstances, the capacity of a recirculation bin and associated cleaning equipment to rapidly handle and clean a deluge of dirty tailings becomes seriously compromised and may, at least temporarily, be exceeded.
In such circumstances, in order to allow the tailings cleaning equipment to “catch up”, such requires drilling to be temporarily halted.
Halting of drilling operations, even for temporary periods, is extremely undesirable, as it results in additional expenses to the well owner considering that drilling operations are typically conducted by rented service rigs, all of which are rented at daily rates. In addition, time may be a factor, considering that drilling operations are typically conducted during winter, when transporting equipment to a site can be done over frozen ground, and removing such equipment from a site need be done before spring thaw.
Accordingly, for the above reasons, stoppage of drilling operations on an operative drilling rig is extremely undesirable.